Thanks to USA TODAY for compiling this list of the number of casualties in each U.S. war:
Civil War: Approximately 620,000 Americans died. The Union lost almost 365,000 troops and the Confederacy about 260,000. More than half of these deaths were caused by disease.
World War I: 116,516 Americans died, more than half from disease.
World War II: 405,399 Americans died.
Korean War: 36,574 Americans died.
Vietnam Conflict: 58,220 Americans died. More than 47,000 Americans were killed in action and nearly 11,000 died of other causes.
Operation Desert Shield/Desert Storm: 148 U.S. battle deaths and 145 non-battle deaths.
Operation Iraqi Freedom: 4,422 U.S. service members died.
Operation New Dawn: 66 U.S. service members died.
Operation Enduring Freedom: 2,318 U.S. service members have died as of May 12, 2014.